This invention relates to apparatus for securing safety lines tethered to workers while performing maintenance or repair.
It is known to use anchors to provide a secure connection of a worker's safety line to a structure on which the worker is performing work. U.S. Pat. No. 1,275,053 to Leiding, for example, discloses a bar type anchor which can be secured across the frame of a window through which a worker passes while washing the window. A safety line or lanyard is connected at one end to the anchor and at the other end to the worker. U.S. Pat. No. 6,233,877 to Monroe, discloses another bar type anchor which is secured across a door frame.
These prior art systems generally work by engaging and pressing outward against an inner surface of the frame forming the opening through which a worker or safety line is to pass and then extending the anchor or securement structure behind the frame on the side of the frame opposite of the side on which the worker will be performing work. In such an orientation, the anchor cannot be pulled through the opening so that the worker, tethered to the anchor, can safely perform the required work.
Railroad hopper cars present unique problems for securing a worker performing maintenance on the hopper car. Hopper cars for storing grain or other granular material, typically have two elongate openings across the top through which the hopper is filled. Lids or covers for the openings are provided for covering the openings during transport. The bottom walls of the hopper car slope downward and inward to allow the contents to flow to one of a plurality of outlet gates in the bottom of the hopper car through which the contents of the hopper car are discharged.
To repair or clean the interior of a hopper car, a worker will access the interior through one of the openings. The sloping walls of the hopper car make it difficult for the worker to find a surface on which it is easy to stand. It is also frequently necessary for the worker to work on the exterior of the hopper car and because of the height of the hopper cars, it is preferable, that such a worker be connected by a safety harness to an anchor. Prior art anchors have been found to be inadequate, because they are only designed for securing a worker on one side of an opening. Moreover, known prior art systems are not designed to allow the worker to work on either side of an opening across which the anchor is secured, when the opening is covered.
There remains a need for an anchor for safety lines that is particularly well adapted for use with railroad hopper cars. In particular, there is a need for such an anchor which can be used to safely connect a worker to the hopper car while working either inside or outside of the hopper car and even when the opening to the hopper is covered.